| Director | Herman Yau |
|---|---|
| Budget | $23 million |
| Box office | $68.1 million |
Bomb disposal officer Cheung Choi-san of the Explosive Ordnance Disposal Bureau (EOD) has been working undercover in a gang of thieves led by Hung Kai-pang, who specializes in bombs.
Cheung coordinates with his handler, Superintendent Chow, and senior inspector Kong Yiu-wai of the Regional Crime Unit, and manages to arrest a number of Hung's underling, including his younger brother, Hung Kai-piu, after performing a cash vault robbery. He also successfully disposes of a bomb, stopping it from detonating.
However, Hung managed to escape arrest and vows for revenge. Six months later, Cheung resumes his position in EOD and is quickly promoted as superintendent of the department and meets a recently divorced primary school teacher, Carmen, and begins to date her.
A year later, Hung has employed a group of mercenary soldiers, delivering morphine and heroin for drug dealers in the Golden Triangle. Man Chung Corporation president Yim Kwok-wing offers him HK$50 million deposit to hijack the Cross-Harbour Tunnel to lure the Hong Kong Government into repurchasing Man Chung's stocks of the Western Harbour Crossing. Meanwhile, after Cheung receives an honor for his undercover duties, Superintendent Chow is killed after a bomb goes off in his car, which Cheung suspects as Hung's doings.
The day after, Hung plants a bomb with a mercury trigger outside of the Revenue Tower, which Cheung successfully disposes, before bringing in three pounds of C4 via a remote control toy truck, which is set to detonate in three minutes. Kong drives Cheung to toss the bomb into Victoria Harbour. Soon after, Hung and his mercenaries hijack the Cross-Harbour Tunnel, trapping hundreds of civilians hostages with 1,000 kg of C4 explosives, placing 500 kg at each entrance of the tunnel.
After making their first killing of a maintenance worker leading to a firefight with the police, Senior Assistant Commissioner of Police Wan Hiu-fung, attempts to negotiate with Hung, who refers himself as "Blast", but Blast demands to speak with Cheung and forces Cheung to release his imprisoned brother by 12AM or he will kill a hostage for every ten minutes late, which Cheung agrees if Blast can promise him to release 100 hostages.
Cheung and Kong escort Kai-piu from prison, who has become a changed man and is reluctant to see his brother, but they were hit by a drunk truck driver on the way, and narrowly makes it back to the tunnel in time before Blast kills a second hostage, but Kai-piu is heavily injured. Blast fulfills his promise and releases 100 hostages, but upon discovering one of them was a young police inspector, Wong Tin-nok, Blasts straps a bomb with four packs of explosives on him. As Blasts sets off the timer to go off in two minutes, Cheung is unable to disable the bomb and Wong is killed by the explosion, devastating several police officers and the press at the scene.
The next morning, the blocked Western and Eastern Harbour Crossing has been opened for the public which strict security checks while Yim is making a fortune when Man Cheung's stocks skyrocket and pays him a commission of HK$500 million. However, Blast is unsatisfied and instructs some of his mercenaries to abduct Yim and force him to transfer HK$1 billion to Blast's bank account before killing him.
In the meantime, Blast also captured Carmen and tied her inside the trunk of a taxi with a grenade in her hand, but Cheung finds and rescues her at a gas station. Blast then demands two helicopters for him to leave a Hong Kong with a couple of hostages including Cheung, and sets off the timer for the 1,000 kg of C4 to go off in an hour until the helicopters arrive.
Cheung then wears some C4 explosives around him and enters the tunnel, threatening Blast to hand out the remote for the 1,000 kg of C4, which startles a couple of the mercenaries and ignites a gunfight where Cheung shoots Blast's leg, while Kong's squad and the Special Duties Unit rush in and takes down the mercenaries while evacuating the civilians, where Kai-piu and some officers and hostages were killed.
Amidst the chaos, Blast shoots Cheung's leg in retaliation and the two exchange fire where Blasts destroys the remote. Blast gains the upper hand when Cheung runs out of ammo and reloads, but Kong severs Blast's arm and the latter is arrested. Cheung rushes to the Hong Kong Island exit of the tunnel while ordering his subordinate, Ben (Ron Ng) to stay at the Kowloon exit and they find the detonating device of the explosives under the trucks at their respective location, but unable to get a clear view.
With less than three minutes before it goes off, Cheung consults the engineer of the tunnel whether the tunnel can sustain 500 kg of C4 exploding, and decides to take a gamble and cut the yellow wire, telling Ben to follow suit if safe. However, the explosives blows up after Cheung cuts the wire, killing him on the spot, so Ben cuts the red wire, but is still heavily injured by the impact. The explosion destroys most of the tunnel but did not affect its structure. Wan announces to reporters that 468 hostages were saved while 38 were killed, along with 43 criminals and 18 officers killed in the incident.
Afterwards, Cheung and other slain officers are given burials at the Gallant Garden where Kong, Carmen, Ben and the others mourn the fallen.